Carolina Parakeet Tasmanian Tiger Gastric brooding frog
Transcription
Carolina Parakeet Tasmanian Tiger Gastric brooding frog
Carolina Parakeet Panthera leo barbaricus Barbary Lion extinct around 1935? (1918?) Extinct 1922 Tasmanian Tiger Gastric brooding frog • • Extinct 1936 Extinct ? Not found since 1985 Table 2.2. A sample of species once thought extinct, but rediscovered. Species name Common name Date # yrs since rediscovered last sighting Dipsochelys hololissa Seychelles giant tortoise 1997 >150 Pterodroma cahow Bermuda petrel 1951 >300 Perameles bougainville Western barred bandicoot 1983 61 Trichocichla rufa Long-legged warbler 2003 109 Gastrolobium lehmannii Cranbrook pea 2001 83 Hapalopsittaca fuertesi Fuertes's parrot 2002 91 Hypsiprimnus gilbertii Gilbert’s potoroo 1994 85 Sida inflexa Virginia pine sida 1999 31 Lepidoptrix (formerly Pipra) vilaboasi Golden crowned manakin 2002 45 Such disappearances and reappearances are common. Keith and Burgman (Keith and Aldabra tortoise Seychelle tortoise Burgman 2004) examined lists of extinct plants in Australia and found that, of 113 species listed as extinct in 1981, only 61 species remained on the extinct list twenty years later. Species were dropped from the extinct list for a variety of reasons including taxonomic revisions, but the most common reason was the rediscovery of remnant individuals. Keith and Burgman humorously named this phenomenon of species reappearing after their supposed extinction the Lazarus effect. Even more surprising than the frequent rediscovery of extinct species is that the majority http://members.aol.com/jstgerlach/tortoise.htm Seychelle saddleback ns with higher spending for biodiversity monitoring, large-bodied species are occasionally covered (Box 2.2). 2.2. Rediscovery of the Ivory-Billed Woodpecker Measuring Current Extinctions It has been described as the “Lord-God” bird and “the grail of birding”. The ivory-billed woodpecker is among the ’s largest woodpecker species. A one-time denizen of the mps and bayous of the southeastern US, this spectacular bird Direct observation are difficult Indirect observation: species - area relationship n unfortunate victim of habitat destruction, as the birds’ mpy habitats were extensively logged and drained during the 1900’s to make way for farms. (Artistic rendition of the -billed woodpecker courtesy of Mark Bowers http://nc- s.gov/birds/ivorybill.html). The last individual to be documented in the United States, an red female, was spotted in 1944. It was later assumed that the Ivory-billed woodpecker had mbed to extinction, joining five other North American bird species thought to have become ct since 1880: the Labrador duck (Camptorhynchus labradorius), Eskimo curlew (Numenius lis), Carolina parakeet (Conuropsis carolinensis), passenger pigeon (Ectopistes atorius), and Bachman's warbler (Vermivora bachmanii). In February 2004, a kayaker paddling through the Cache River National Wildlife Refuge Species-Area relationship ntral Arkansas spotted an unusually large woodpecker with markings resembling those of Species-Area relationship ory-bill. Word of his sighting spread and aroused the curiosity of leading bird experts. S = c × Az S = c × Az after, additional sightings were made and expeditions were organized by scientists from izations including the Cornell Lab of Ornithology and The Nature Number of species S c is a taxon specific constant z is the extinction coefficient Conservancy. is in the range In 0.1 to 0.3 on to extensive searching, the researchers set out arrays of remote cameras and sound c is a taxon specific constant z is estimated using the slope log(Number of species S) Chapter 2 – Page 19 Area A log(Area A) Mac Arthur and Wilson (1967): the theory of island biogeography Fig 4.5 Small mammals in forest granivores all small mammals r2 = proportion of variation explained Estimating extinction rates Estimating how many species go extinct Snow Log(Number of species S) Soriginal Log(Area A) Snow Soriginal cAznow = cAzoriginal = Aznow Azoriginal Snow = Soriginal Log(Number of species S) Aznow Azoriginal Log(Area A) using z=.15 (this is arbitrary) deforestation = 1.8% per year (Anow / Aoriginal = 98.2/100) 10 million species (Soriginal) Snow = 9,973,000 Difference between Snow and Soriginal = 27,000 species per year Causes of extinction? 88 46 20 14 Disease Overharvest Pollution Exotic species 2 Habitat destruction and degradation Percent of species affected Causes of endangerment 100 90 80 70 60 50 40 30 20 10 0 Causes of extinction 88 46 20 Habitat destruction 14 Disease Overharvest Pollution Exotic species 2 Habitat destruction and degradation Percent of species affected Causes of endangerment 100 90 80 70 60 50 40 30 20 10 0 habitat loss (less area = fewer species) Causes of extinction Habitat destruction habitat loss (less area = fewer species) habitat fragmentation Fringed prairie orchid Causes of extinction Fig 55.6 Forest cover of Cadiz Township in Wisconsin Habitat destruction habitat loss (less area = fewer species) habitat fragmentation Edge effects Fragmentation Fig 4.5 Small mammals in forest granivores all small mammals r2 = proportion of variation explained Causes of extinction Habitat destruction Habitat loss (less area = fewer species) Habitat fragmentation Edge effects Isolation Exotic species 88 Exotic species: species introduced to regions outside of their native range 46 20 14 Invasive species: an exotic species with strongly increasing populations (and most often detrimental effect on the native species or habitats) Disease Overharvest Pollution Exotic species 2 Habitat destruction and degradation Percent of species affected Causes of endangerment 100 90 80 70 60 50 40 30 20 10 0 Exotic species Invasive species Brown tree snake Kudzu Introduced to Guam, predated and eradicated all native endemic bird species Introduced to the SouthEast USA for their edible leaves and pretty flowers. Overgrowing forests, changing native habitats Zebra mussel Introduced through boats into Great Lakes, clogging up water intakes, removing food more effective out of water column than natives. Pollution Point sources 88 Non-Point sources 46 20 14 Disease Overharvest Exotic species Pollution 2 Habitat destruction and degradation Percent of species affected Causes of endangerment 100 90 80 70 60 50 40 30 20 10 0 Pollution Pollution Air Water Global warming Acid rain Ozone depletion, smog, .... Pollution Heavy metal Water Body Species Women of childbearing age, young children One per month All Other Individuals (# of meals)* Lake Iamonia Largemouth Bass !Lake Jackson Black Crappie, Bluegill, Largemouth Bass Bluegill Largemouth Bass One per month One per week Two per week One per month Two per week One per week Lake Munson Black Crappie, Redear One per month Sunfish One per week Moore Lake Largemouth Bass One per week Lake Miccosukee http://www.myfloridaeh.com/community/fishconsumptionadvisories/FWFGuide.htm One per month One per week Water Toxins Nutrients eutrophic vs oligotrophic PRESS RELEASE, JULY 26, 2004 LOUISIANA UNIVERSITIES MARINE CONSORTIUM AVERAGE SIZE "DEAD ZONE" IN ANYTHING BUT AN AVERAGE YEAR The coast-wide extent of the Louisiana "dead zone" mapped this week is slightly larger than average at 15,040 km2 (5,800 square miles). The long-term average since mapping began in 1985 is 13,000 km2 (5,000 square miles). The river flow and the offshore conditions prior to the mapping cruise were anything but normal and were more reminiscent of the Great Mississippi River Flood of 1993. The river in 2004 peaked in discharge several times in January, February, March and May, followed by a prolonged above average flow that persisted from June into July, as in 1993. Exploitation Commercial Incidental Exploitation Bycatch: albatross, whales, .... Predator control in parks Recreation Pets Recreational Diseases Causes of extinction (Atelopus zeteki) Habitat destruction Chytrid, a fungus, is believed to be one of the sources for amphibian decline Exotic species Pollution Exploitation www.clemetzoo.com/conservation/project_golden_frog.asp Diseases